First: what 27.0.1 fixed, and what it didn’t
Many installed 27.0.1 expecting it to fix everything. The official notes are short: the update fixes the iPhone 18 Pro / Pro Max restart when Face ID fails, a colour artifact on photos taken at 2x and a touch issue.
Battery, heat, the keyboard or freezing apps aren’t on the list. So if you have one of these problems, it’s not „27.0.1 not working”: it simply wasn’t built for them. The next real chance is iOS 27.1.
What’s being reported, and what to do for each
These come from forums, Reddit and user groups. Not everyone has them: many say iOS 27 runs even better than 26 on their phone.
Why: Post-update reindexing (Photos, Spotlight) and iCloud sync, especially in the first 2–3 days.
What to do: Give it 3–5 days, then check Settings → Battery for what’s using power. Restart once indexing has finished.
Why: The same background processes; with a worn battery, the effect is stronger.
What to do: Avoid heavy use while charging in the first days. If it still runs hot at idle after a week, have it checked.
Why: Reported by many users; no official fix yet.
What to do: Restart and try without haptic feedback: Settings → Sounds & Haptics → Keyboard Feedback.
Why: Shows up mostly with tinted or clear icons (Liquid Glass).
What to do: Temporarily switch to the default icons and restart.
Why: Apps not yet adapted, or data corrupted after the update.
What to do: Force-close the app, update everything from the App Store, restart; reinstall if needed.
Why: On iPhone 18 Pro, the restart bug was fixed in 27.0.1. On other models it can be software or a TrueDepth module problem.
What to do: Reset Face ID (Settings → Face ID & Passcode → Reset Face ID), restart and set it up again. If you see „Face ID is not available”, it’s almost certainly hardware.
Why: Reported mostly on iPhone 15 Pro.
What to do: Turn Auto-Brightness off and on again (Settings → Accessibility → Display & Text Size).
Why: The carrier profile or eSIM reset during the update.
What to do: Airplane Mode for 15–30 seconds, update carrier settings (Settings → General → About), reset network settings if needed.
The battery: the biggest complaint
Fast drain is complaint number one, reported on very different models, from iPhone 14 Pro Max to 17 Pro Max and iPhone Air. Part of it is explainable: after any update, the phone reindexes photos and search and finishes setup in the background. Apple even says the Battery page can show the update is still in progress and recommends a few days before judging battery life.
But there’s the other half of the story, which we see daily in the workshop: an already worn battery suffers most after a big update. On a phone with battery health at 75–80%, the extra load of the first days hits twice as hard: faster drain, more heat, sometimes sudden shutdowns. The update didn’t ruin the battery; it just revealed it was already tired.
Check it yourself in 10 seconds: Settings → Battery → Battery Health. If you see below 80% or „Service”, your battery-life problem probably isn’t just iOS 27. See a real case: an iPhone 14 brought from 59% to 100%.
Face ID: when it’s software and when it’s hardware
On the iPhone 18 Pro and 18 Pro Max, the failed-Face-ID restart bug is confirmed and fixed in 27.0.1. Details in our dedicated article.
On other models (for example iPhone 16 Pro Max), users also report Face ID stopping after the update, but there’s no Apple-confirmed bug here so far. First step: reset Face ID (Settings → Face ID & Passcode → Reset Face ID), restart and set it up again. If the phone shows „Face ID is not available”, or the problem stays after the reset, it’s very likely a TrueDepth module problem (for example after a drop or moisture), and no update will fix that.
So: keep updating or not?
We understand the urge to „freeze” the phone on an old version; we see it often in the comments. But staying months without updates leaves you without security fixes. A reasonable strategy:
Not on day one
For a major version (27.0), wait a few days to see what others report.
Back up first
iCloud or computer. If something goes wrong, you lose nothing.
But don’t skip them
Security fixes matter. Install them, just not in a rush.
When it’s no longer „just the update”
- • The phone runs hot even at idle, more than a week after the update.
- • Battery health is below 80% or shows „Service”.
- • The message „Face ID is not available” appears.
- • The phone shuts off suddenly at a still-high percentage or won’t turn on.
In any of these cases, the problem is most likely hardware and worth checking, no update will fix it.
Radical Service, services and guides
Sources: MacRumors (iOS 27.0.1), The Mac Observer (reported bugs), Cybernews, MacRumors (iOS 27.1). Community reports are not confirmed by Apple; the situation may change with upcoming updates.